Mafia secrecy functions as product credibility signaling, not cultural tradition.

Evidence

Similar reasoning applies to secrecy. While secrecy is the most elementary means of practicing self-protection, vis-à-vis both rivals and the state, it is primarily a requirement for selling protection to others, for if our customers know anything which can be used against us, our position as guarantor is weakened since it is difficult to control someone who can fight back. Leading a discreet life, allowing only creditable information to filter out—these are essential prerequisites for selling our product. Omertà is not, as many have suggested, merely a traditional code which has matured over long periods of foreign domination and is now inertially retained, nor is it simply a means of keeping the state out of our business. It is a crucial part of our ability to serve as an entrepreneur of protection. This is one of the differences between selling protection and selling cars. Whereas in the latter case our private life is not necessarily an indication of how reliable our cars will be, in the case of protection, although what is considered honorable may be historically mutable, what we are—or what we appear to be—counts as one of the most important signs of good faith. — Diego Gambetta, The Sicilian Mafia The Business of…, 101

Categorization

• DEFINE: Reframes omertà from folk-cultural explanation to an economic signaling function — the guarantor’s private conduct is the product’s quality signal.
• XREF: Connects to Milgrom et al. on reputation/information as the currency of third-party enforcement, and to Schelling on credibility of commitments — the guarantor’s vulnerability is what makes his bond credible.
• ADDENDUM: Directly supports the reader’s thesis: omertà is the informational asymmetry that makes the private judge’s bond credible — an extension of the law-merchant private-judge model.